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Species Profile - Stygimoloch

Species Profile - Stygimoloch

All I know about this dinosaur, the Stygimoloch, is that its name is derived from hell and a demon. And that's why I like it.
- Cabot Finch

Stygimoloch is a genus of pachycephalosaurid dinosaur that originated from Late Cretaceous North America. The second-largest pachycephalosaur of the Hammond Foundation, Stygimoloch was cloned by InGen for exhibition at Jurassic World on Isla Nublar. Stygimoloch specimens were encountered on the island during the destructive volcanic eruption of Mount Sibo in 2018.[1]

Stygimoloch is rewarded for progressing through the Entertainment Division on Isla Tacaño, and upon being researched, can subsequently be excavated at the Hell Creek and Lance Formations in North America.

The Stygimoloch was first added to the game with the Fallen Kingdom Dinosaur Update.


Originally from the Late Cretaceous period of North America, Stygimoloch was cloned by InGen for Jurassic World on Isla Nublar, where it lived alongside its close relative Pachycephalosaurus. After the disastrous incident that took place in 2015, Stygimoloch and the park's other resident dinosaurs were released to the wild and were considered an endangered species at the time of the eruption of Mount Sibo.[1]

At least five Stygimoloch were successfully transported by a team of mercenaries hired by Eli Mills to the Lockwood Estate in northern California, where the surviving dinosaurs were intended to be auctioned off. However, Claire Dearing and Owen Grady released an individual named "Stiggy" from its cage, and it subsequently went on a rampage throughout the manor, disrupting the auction and causing numerous injuries before fleeing into the surrounding forest. The other Stygimoloch were eventually freed by Maisie Lockwood alongside all the other dinosaurs.[1]


Stygimoloch is a small bipedal herbivore with a large domed head. It has a prominant crown of horns around its dome and snout. The base genome of the Stygimoloch is a chestnut brown body with cream underbelly and dark brown streaks on its back.


Stygimoloch is one of the more social pachycephalosaurs, second only to Homalocephale and can live in medium-sized to large groups. They are tolerant of a fair number of other dinosaurs. However, they will fight with small carnivores and are defenceless against much larger carnivores.


Stygimoloch is a dubious genus of Pachycephalosaurid due to a recent studies in 2009 and 2016, suggesting that both Dracorex and Stygimoloch are juvenile forms of Pachycephalosaurus. The idea is strengthened from the fact that only juvenile fossils of Dracorex and Stygimoloch have so far been found. Furthermore, an unopposed study conducted in 2010 suggests that all flat-headed Pachycephalosaurids were juvenile stages of dome-headed adults, thus supporting the notion that Stygimoloch was instead a juvenile Pachycephalosaurus as the horns were absorbed by the growing dome.

The name Stygimoloch means 'Demon of the River Styx', in reference to the Hell Creek formation where it was found and its ring of horns around its bony dome, giving it a devilish look.


Stygimoloch lived alongside many other Late Cretaceous dinosaurs, including the hadrosaur Edmontosaurus, the ceratopsians Triceratops and Torosaurus, the armored Ankylosaurus, the ornithomimid Struthiomimus, as well as the theropods Troodon and Tyrannosaurus.





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